[llvm] [VPlan] Preserve trunc nuw/nsw in VPRecipeWithIRFlags (PR #144700)

[Luke Lau via llvm-commits]

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@@ -612,6 +613,13 @@ class VPIRFlags {
     WrapFlagsTy(bool HasNUW, bool HasNSW) : HasNUW(HasNUW), HasNSW(HasNSW) {}
   };
 
+  struct TruncFlagsTy {
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lukel97 wrote:

I tried this but the constructors take in WrapFlagsTy etc. and differentiate the type based on this. I tried adding a boolean `isTrunc` flag for that specific constructor but it seemed kind of hairy. What do you think?

https://github.com/llvm/llvm-project/pull/144700